Evolution of paroxysmal nocturnal hemoglobinuria clone during an hemolytic crisis in a patient with aplastic anemia. Flow cytometry study
Canalejo, K.; Galassi, N.; Riera, N.; Bengió, R.; Aixalá, M.
Medicina 61(5 Part 1): 581-584
2001
ISSN/ISBN: 0025-7680 PMID: 11721326 Document Number: 533162
The expansion of paroxysmal nocturnal hemoglobinuria (PHN) clone was evaluated in a patient with aplastic anemia (AA) of 18 years of evolution during an hemolytic crisis. On day 0, Ham and Sucrosa tests were positive and hematological parameters were altered. Low hemoglobin (Hb) levels and erythrocyte and leukocyte counts were found and continued decreasing on days 7 and 24 (last day of study). High LDH levels, indirect bilirubin and reticulocyte counts were detected throughout. We evaluated CD55 and CD59 on erythrocytes by flow cytometry. Our results showed low CD55 expression with respect to the normal pattern. Since day 0, CD59 staining detected two red cell populations: PNH I (48%), cells with positive fluorescence similar to normal and PNH III (52%), negative cells (PNH clone). These negative cells increased, reaching 70% on day 24. Other membrane anchored leukocyte proteins were also absent (CD14) or decreased (CD16). We found a good correlation between clinical observations, evolution of the laboratory values and expansion of the PNH clone.